Cloud computing, enterprise networks, and data center networks continue to drive increased bandwidth demand of optical waveguides for metro and long haul wires, and also rack-to-rack wires within data centers to 100 Gbps and beyond. Increased bandwidth demand has motivated overall high data transmission speed on entire optical systems.
Optical interconnect techniques continue to gain attention as potential solutions for high-speed data transmission between systems, and over a variety of distances. For example, optical interconnect solutions have been proposed for a number of applications, such as between racks in a data center, between household consumer electronics, and between boards or chips within server systems. Optical interconnects are particularly suitable for adoption within transmitter and receiver systems.
In a conventional optical sub-assembly (OSA) design, a transmitter module includes a transmission laser, a driver integrated circuit (IC), and a printed circuit board (PCB), while a receiver module includes a photodetector (PD), a trans-impedance amplifier (TIA), and a PCB. The optical path between the transmission laser (commonly a vertical cavity surface emitting laser (VCSEL)) and PD is typically an optical fiber, such as a fiber ribbon and optical waveguides. Complex beam routers including a focusing lens, a prism, and a fiber connector are used to precisely align the optical fiber with the optical path. Mechanical structures including screws, clips, alignment pins and structural housing are commonly used to secure and align the beam routers.
However, an optical interconnect typically requires coupling of fiber assembly and lasers which involves an external lens alignment, adding complexity and energy loss. It becomes more complicated if multiplexing is involved. A less complicated assembly technique with multiple output ports is needed to improve efficiency and reduce cost.